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Fitch, Val Logsdon

Val Logsdon Fitch

In 1980, American nuclear physicist Val Logsdon Fitch (born 1923) was co-recipient with James Watson Cronin of the Nobel Prize for Physics. The two men received international recognition in the scientific community as a result of an experiment they conducted in 1964 that showed that certain sub-atomic reactions are not indifferent to time. They did this by studying the decay of particles called K-mesons and demonstrating that reactions run in reserve do not simply follow the backward path of the original reaction. Their results had tremendous impact on world knowledge by disproving long-standing scientific theories.

Early Life

The youngest of three children, Fitch was born March 10, 1923, on a cattle ranch in Cherry County, Nebraska, near the South Dakota border. His father, Fred Fitch, was a cattle rancher and his mother was a school teacher. Fred Fitch bought his four-square-mile ranch when he was only 20 years old.

The family ranch was situated in a sparsely populated part of the United States and far from any large communities. Also, the expanse was located near a site of historical significance: 20 years earlier and only 40 miles away the battle of Wounded Knee had taken place. As such, the Sioux Indians were a large and integral part of the community, and Fred Fitch became friendly with the local Native Americans. He learned their language and eventually was named an honorary chief.

Val Fitch later remarked that the remoteness and vastness of his early environment made a big impression on him. He also commented that his memories of cattle ranching were rather mundane and far removed from the romanticized myths of the American West. Rather than stirring cattle roundups, Fitch remembered rather unexciting chores such as oiling windmills and fixing fences. "E.B. White has defined farming as 10 percent agriculture and 90 percent fixing something that has gotten broken," noted Fitch in the autobiography he penned on the occasion of receiving his Nobel Prize.

Shortly after Val Fitch was born, his father suffered a serious injury in a riding accident. This limited his physical capabilities, and he couldn't perform many of the more arduous activities involved with running a ranch. Because of this, Fred Fitch entered the insurance business and moved his family about 25 miles away to Gordon, Nebraska. The cattle ranch remained within the family, but its operation was left to others. While living in Gordon, Val Fitch began his public schooling. He developed an interest in chemistry, but his scientific pursuits would turn to physics in the 1940s when he entered the U.S. Army in World War II.

Worked on the Manhattan Project

One of the most significant periods in Val Fitch's early adulthood took place during the war. While serving in the Army and stationed in Los Alamos, New Mexico, he worked on the Manhattan Project. The U.S. government began the project in 1942 in response to the growing concern that the Axis powers were close to developing atomic weaponry. The project, operated by the Army Corps of Engineers, was designed to develop an atomic bomb before Germany or Japan. Noted physicist J. Robert Oppenheimer (1904–1967) directed the construction and test of the first A-bomb at the Los Alamos laboratory.

Fitch worked under the direction of nuclear physicist Sir Ernest William Titterton (1916–1990), who was a member of the British Mission. Fitch found his involvement "stimulating." He toiled in a small laboratory as a technician, and had the privilege of working with some of the greatest names in the physics field, including Enrico Fermi, Neils Bohr, James Chadwick, Isidor Rabi, and Richard Tolman. Fitch's experience was recounted as part of a chapter in a book called All in Our Time, edited by Jane Wilson and published by the Bulletin of Atomic Scientists.

In all, Fitch spent three years at Los Alamos, learning the techniques of experimental physics. While stationed there, he came to a conclusion that would play a large part in directing his future career. He realized, as he later recalled, that the most successful scientists were the ones who knew the most about electronics. Appropriately, he set about learning all he could about electronic techniques, an educational experience that enabled him to use new technology while measuring new phenomena. More significantly, it opened his mind to a new way of thinking. As he recalled in his Nobel autobiography, he learned how to "allow the mind to wander freely and invent new ways of doing the job."

Studied with Noted Scientists

After being discharged from the Army, Fitch began his formal education at the graduate and post-graduate levels. While at Los Alamos, Fitch also worked with Robert Bacher, the group leader of Weapons and Experimental Physics division. After the war, Bacher offered Fitch a graduate assistantship at Cornell University in Ithaca, New York. However, before he could begin the work, Fitch needed to obtain an undergraduate degree at McGill University in Montreal, Quebec, Canada. He received a bachelor's degree in electrical engineering in 1948.

While at McGill, another graduate opportunity soon presented itself and instead of going to Ithaca, Fitch headed off to Columbia University in New York City, where he worked on his Ph.D. thesis with James Rainwater (1917–1986), another nuclear physicist who worked on the Manhattan Project. (Rainwater would receive the 1975 Nobel Prize in Physics). At Columbia, Fitch made some more valuable academic connections. Rainwater shared his university office with Niels Bohr (1885–1962), whose work on the structure of atoms earned him the 1922 Nobel Prize in Physics. Bohr introduced Fitch to the work of John Wheeler (born 1911), the theoretical physicist who would later increase the understanding of black holes by using the concepts of relativity. Specifically, Fitch became familiar with Wheeler's paper about 5-mesic atoms. Through his exposure to Wheeler's work, Fitch developed his own thesis on 5-mesic atoms.

The opportunity to work with such renowned names in the field proved a pivotal part of Fitch's education. At the same time he was introduced to very new and crucial technical advancements including the Columbia Nevis cyclotron, sodium iodide with thallium activation, and new phototubes. During this period, combining the knowledge gained at Los Alamos with his university education, he designed and built the gamma-ray spectrometer, a multichannel pulse height analyzer. Working with colleagues, Fitch helped develop a technique for precise gamma-ray measurements to obtain a better mass value for the 5-meson. From there, his interests turned to strange particles and K mesons, an area he enjoyed because it was unpredictable and challenging.

Studied K-mesons

Fitch was awarded a Ph.D. in physics by Columbia University in 1954. That same year, he became a faculty member at Princeton University in New Jersey. For the next 20 years, he worked with graduate students researching K-mesons. This eventually resulted in unexpected findings that would eventually lead to the discovery of CP-violation, which earned him the Nobel Prize. The unexpected was what he found most compelling about his work. "At any one time there is a natural tendency among physicists to believe that we already know the essential ingredients of a comprehensive theory," he once wrote. "But each time a new frontier of observation is broached we inevitably discover new phenomena which force us to modify substantially our previous conceptions. I believe this process to be unending, that the delights and challenges of unexpected discovery will continue always."

The unexpected could also be said to apply to his life. Looking back on his early years in Nebraska, he found it remarkable that someone who grew up on a cattle ranch would eventually travel to Stockholm, Sweden to receive the Nobel Prize in physics.

Collaborated with Cronin on Groundbreaking Experiment

Fitch encountered the unexpected most profoundly, perhaps, in the work that led to his Nobel Prize. The experiments that led to the recognition began in 1963. Results were published in 1964. Fitch collaborated with particle physicist James Cronin (born 1931). The two men used the Alternating Gradient Synchroton (AGS) housed at the Brookhaven National Laboratory in New York to study the properties of K0 mesons. Working together, they helped modify the prevailing belief that the laws of symmetry and conservation are unbreakable. According to one of these laws (the principle of time invariance [designated T], particle interactions should be indifferent to the direction of time. For a long time, it had been accepted that this symmetry and two others, those of charge conjugation (C) and parity conservation (P), governed all the laws of physics. In their experiments, Cronin and Fitch showed that in rare instances subatomic particles called K mesons violate CP symmetry during their decay. This was the opposite of what they expected to find. They had originally intended to confirm CP symmetry by demonstrating that two different particles did not decay into the same products. Their data demonstrated the unexpected result that, sometimes, the long-lived neutral K meson does decay into two pi mesons. Thus, decays of K0L mesons sometimes violate the known rules, and so are different from all other known particle interactions. This became known as the CP Violation. This shook the core belief of physics that the universe is symmetrical. Later, their results would be verified in similar experiments conducted at other laboratories by other scientists.

Honored for his Work

Between the publication of the experiment's results and the 1980 Nobel Prize, Cronin and Fitch received the Research Corporation Award for their work on CP violation. In 1968, Fitch received the Ernest Orlando Lawrence Award for his research on mesons. He was recognized for adding to the world's knowledge of both mesons and nuclear structure and for demonstrating the fundamental asymmetry of nature under the combined transformation of charge conjugation and parity. In 1976, Fitch and Cronin were awarded the John Price Witherill Medal of the Franklin Institute.

Fitch would garnered many honors and distinctions during his career. He was named a fellow of the American Physical Society and the American Association for the Advancement of Science, and he became a member of the American Academy of Arts and Sciences and the National Academy of Sciences. In addition, at Princeton University, he garnered the titles of Cyrus Fogg Brackett Professorship of Physics and James S. McDonnell Distinguished University Professor of Physics. In 1976, he was appointed chairman of the Physics Department. For 50 years (1947–1997), he was actively involved with the Board of Trustees of Associated Universities, Inc., which managed Brookhaven National Laboratory. From 1961–1967 and 1988–1991, he was a trustee. From 1991–1993, he served as Chairman of the Board. In 1993, he returned to the Board as a member. In 2000, he received an honorary degree (Doctor of Science) from Princeton University.

Advocated for Global Reform and Peace

As the 20th Century drew to a close, Fitch grew very concerned about world affairs and he became a sponsor for the Coalition for Peace Action, an grassroots citizens' organization headquartered in Princeton, New Jersey, that advocates global abolition of nuclear weapons, a peace economy, and a halt to weapons trafficking at home and abroad.

In October 1999, he and 31 other Nobel laureates in physics urged the Senate to approve the Comprehensive Test Ban Treaty. In July 2000, he joined 49 other Nobel laureates in signing a letter to President Clinton urging him not to deploy an anti-ballistic missile system during the remaining months of his administration. The signers felt the system was ineffective, would be harmful to the nation's security, and would initiate a new arms race. In December 2001, on the 100th anniversary of the Nobel Prize, Fitch was among the 100 Nobel laureates who issued a written call for environmental and social reform as a means to achieve world peace. In January 2003, he and 40 other Nobel laureates in science and economics issued a declaration opposing United States going to war against Iraq without wide international support. In the brief declaration, the signers wrote: "The undersigned oppose a preventive war against Iraq without broad international support. Military operations against Iraq may indeed lead to a relatively swift victory in the short term. But war is characterized by surprise, human loss and unintended consequences. Even with a victory, we believe that the medical, economic, environmental, moral, spiritual, political and legal consequences of an American preventive attack on Iraq would undermine, not protect, U.S. security and standing in the world.

Fitch has two sons from his first marriage (to Elise Cunningham who died in 1972) and three stepchildren from his second marriage (to Daisy Harper, in 1976).


"James Watson Cronin,", (December 10, 2003).

"Nobel Laureates Warn Against Missile Defense Deployment," Federation of American Scientists, (December 10, 2003).

"Nobel Winners Urge Halt to Missile Plan," Yorkshire CND, (December 10, 2003).

Press Release: The 1980 Nobel Prize in Physics, Nobel e-Museum, (December 10, 2003).

"Val Fitch—Autobiography," Nobel e-Museum, (December 10, 2003).

"Val Logsdon Fitch,", (December 10, 2003).

"Val Logsdon Fitch,", (December 10, 2003).

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"Fitch, Val Logsdon." Encyclopedia of World Biography. . 28 Apr. 2017 <>.

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Fitch, Val Logsdon

Val Logsdon Fitch, 1923–2015, American nuclear physicist, b. Merriman, Neb., Ph.D. Columbia, 1954. During World War II Fitch was drafted into the army and worked on the detonator for the atomic bomb at Los Alamos. After receiving his doctorate, he joined (1954) the faculty at Princeton, where he remained until he retired (1993). Fitch and co-researcher James Watson Cronin were awarded the 1980 Nobel Prize in Physics for a 1964 experiment that proved that certain subatomic reactions do not adhere to fundamental symmetry principles. Specifically, they proved, by examining the decay of K-mesons, that a reaction run in reverse does not merely retrace the path of the original reaction, which showed that the reactions of subatomic particles are not indifferent to time. The results also helped explain why matter-antimatter collisions in the aftermath of the big bang did not destroy all matter in the universe.

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"Fitch, Val Logsdon." The Columbia Encyclopedia, 6th ed.. . 28 Apr. 2017 <>.

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"Fitch, Val Logsdon." The Columbia Encyclopedia, 6th ed.. . Retrieved April 28, 2017 from